Honda Acura NSX 1991 Service Manual page 48

Variable Valve Timing and Lltt tlectronlc
Control System (VTEC)
Outline
The engine is equipped with multiple cam lobes per cylinder, providing one valve timing and lift profile at low speed and a
different profile at high speed. Switch-over from one profile to the other is controlled electronially, and is selected by
monitoring current engine speed and load.
5-4